HES1 and central nervous system cancer: Hes1 overexpression has been reported in numerous tumors including colon cancer [20–22], breast cancer [23], hepatocellular carcinoma (HCC) [24], glioma [25], non–small cell lung cancer [26], head and neck squamous cell carcinomas [27], ovarian carcinomas [28], meningiomas [29], and medulloblastomas [30], suggesting the oncogenic activity of Hes1.